Atomic Theory
Who was the first scientist to contribute to atomic theory? (Hint: His model is called the billiard ball model)
John Dalton
Dense, positive center of the atom
nucleus
What do we call an atom that has a net charge?
ion
Who is credited for the creation of our modern periodic table?
Dmitri Mendeleev
Which subatomic particle will NEVER be the same for different elements on the periodic table?
protons
JJ Thomson discovered the presence of the first subatomic particle, which was it?
Electrons
Which subatomic particle has the least mass?
electron
What does the number next to the name of an isotope represent.
Ex: Oxygen - 18
Isotope's atomic mass
These are a class of element that are located on the "stair steps" of the Periodic Table.
Metalloids
Which element is most likely to be found within compounds in nature?
A) Carbon
B) Nitrogen
C) Chlorine
D) Aluminum
C) Chlorine
(It is a Halogen - the most reactive nonmetals on the periodic table)
Who discovered that atoms have a dense, positive center called the nucleus?
Ernest Rutherford
In a neutral atom, which 2 particles will always equal each other?
protons and electrons
Nitrogen-14 and Nitrogen-15 are isotopes. What will be the same and what will be different about them?
same number of PROTONS but different number of NEUTRONS.
Which family contains the most reactive metals on the periodic table?
Alkaline Metals
2 electrons on first energy level
8 electrons on second energy level
7 electrons on third energy level
Who researched electrons and came up with the planetary model of the atom?
Niels Bohr
This is the most accurate, most current model of an atom that shows us the most likely location of electrons in an atom
electron cloud model
4 protons
6 electrons
Why do elements in the same family share similar characteristics?
They share the same number of valence electrons
Draw a Bohr Model for the following ion Al+3
Since Al+3 has lost three electrons, it will only have 10 electrons in total.
2 on the first energy level, 8 on the second energy level
This scientist discovered the final subatomic particle, the neutron?
James Chadwick
Sodium (Na) has an atomic number of 11 and an atomic mass of 23.
How many protons, neutrons, and electrons are in an atom of Sodium?
11 protons
11 electrons
12 neutrons
How does an atom get a charge to become an ion?
by gaining or losing electrons
Why does helium belong in the noble gases family if it only has 2 valence electrons?
Because it's outermost energy level is full, like all other noble gases.
Why is the atomic mass for each element on the periodic table expressed as a decimal?
It is a weighted average of all natural isotopes of the element